Like any other plant, Cannabis requires certain vital nutrients to boost its growth and development stages to have the desired yield. These essential nutrients range from macro-nutrients (NPK), secondary essential nutrients, and micro-nutrients.

The following rundown encloses a detailed explanation of How and When to apply each vital nutrients and of what optimum quantity.

Vital Macro-Nutrients

This particular type of essential nutrient is needed in much greater quantity as compared to the other types. Here, the gardener administers the nutrients in handy when needed. Besides, the environment produces other kinds of macro-nutrients that are not given directly by the gardener.

  • The air is a mixture of gases, and supplies the garden with enough Oxygen (O), Nitrogen (N) and Hydrogen (H).
  • Usually, the main components of macro-nutrients are Nitrogen, Phosphorus, and Potassium denoted as NPK. Most artificial fertilizers are designed to have these three components in their respective percentages.

Amounts NPK needed at each stage.

Cannabis needs different amounts of essential macros depending on the stage of development. Nitrogen is needed in higher quantities during the vegetative and bud-forming stages than during the flowering stage.

For its part, phosphorus is needed more during the flowering stage and is only required at about half the ratio of N levels during the vegetative phase of development. During this phase, K is needed at between half and two-thirds the level of N.

Secondary Nutrients

These kinds of nutrients are needed in a much smaller amount than the main elements (N-P-K) as compared to the macro types.

These nutrients are very important at each stage of growth of the cannabis plant so, they should not be neglected no matter the stage (flowering, budding, seeds, etc.).

The main components are; Calcium (Ca), Magnesium (Mg), and Sulfur (S). Like the macro-nutrients, each kind of these secondary nutrients plays a very specific role in the growth and development of the plant.
Calcium assists in transporting other nutrients and aids in their absorption. Magnesium is a critical component of chlorophyll. Sulfur aids in the transport of chlorophyll, but also assists with plant metabolism and transpiration.

Components of Micronutrients


Calcium is the most abundant nutrient in the plant body as it is found in the root, leaves and even makes up the cell membrane. It aids in;

  1. Combating pest and illness
  2. Strengthen cell wall structure, leaves, and stems
  3. Improves other nutrients absorption
  4. Regulate enzyme action.


Another vital element needed for cannabis growth and mainly found in the leaves is magnesium.  Because of its position, it aids in creating energy for growth during photosynthesis. Magnesium is a very important component of chlorophyll molecule hence if magnesium levels are low; the cannabis plant will struggle to grow.


The most essential nutrient in the vegetative stage is sulfur however; this does not mean that the cannabis plant does not need sulfur during the seedlings and flowering phase. Because it is slowly moving throughout, sulfur’s deficiency mostly affects younger leaves first and the symptoms are; yellowing leaves and curl leaf tips on the more affected leaves.

pH and Nutrient Availability

The pH is a measure of the acidity or alkalinity of soil or growing medium. As important as nutrients if not more so, is the pH of the soil or media the cannabis is growing in. Depending on the growing medium, pH needs to be check as to be much compatible with the medium if not the plants might not survive it.

Hydroponics growing

In this kind of media, adjustments, and keen attention on the pH range is recommended as the plant changes from one phase to another. The pH level should be increased as one growth stage leads to another until a maximum pH of 8 is attained.

  • During the early development of a cannabis plant, an optimum pH of 5.4 is best. This aids in the production of roots, cell membranes and stems and leaves strengthening.
  • As the plant approaches the flowing stage, much energy is required hence; the chlorophylls are expected to function best. On this regard, magnesium is highly needed so, the pH needs to be step up from 5.4 to 5.8
  • Around the vegetative growth stage, transpiration, metabolism, and overall growth is observed. Here, the plant needs much of Sulfur than ever before so, the pH again is been shifted from 5.8 to about 8 maximum.

Growing in Soil

With the soil-growing medium, much attention on the pH is not recommended as an optimum pH of 6.0 to 6.5 is ideal no matter the growth phase.